The present invention relates to plugs for closing openings or holes in sheet metal panels, in wood panels, and the like.
It is common to provide sheet metal panels or walls, or wood panels or walls, with openings which are covered with plugs when not in use. When it is desired to place an opening to a practical use, the corresponding plug is removed to uncover the opening.
Various types of plugs have been provided in the past, for that purpose, such as disclosed for example in U.S. Pat. No. 1,800,173 and 3,168,961. Such plugs are generally either stamped of sheet metal or molded of plastic, provided with a domed body and an integral shank or with fingers, sometimes provided with barbs, steps and like side protrusions which retain the plug in position over the opening or hole after the shank or fingers have been inserted in the opening or hole.
It is desirable that such plugs be manufactures in great quantity at as low a cost as possible, while still being attractive in appearance, being capable of ready manual insertion, and capable of being held securely once the shank or fingers are inserted in an opening or hole.